Work vehicle

ABSTRACT

A work vehicle allows an operator to easily check the vertical position and the angle of bucket. The work vehicle includes a front loader with a bucket, and freely raises/lowers and rotates the bucket. The work vehicle comprises a display disposed near an operator seat. The display is configured to display vertical position information and angle information of the bucket.

This is the U.S. national stage of application No. PCT/JP2015/079643,filed on Oct. 21, 2015. Priority under 35 U.S.C. § 119(a) and 35 U.S.C.§ 365(b) is claimed from Japanese Application No. 2014-218763, filedOct. 27, 2014, and Japanese Application No. 2015-106874, filed May 26,2015, the disclosures of which are also incorporated herein byreference.

TECHNICAL FIELD

The present invention relates to a work vehicle, and more particularly,to a work vehicle having a display.

BACKGROUND ART

Conventionally, tractors have been known as a representative example ofwork vehicles. Tractors can be equipped with a work machine having abucket. The tractors carry earth and soil by raising/lowering androtating the bucket (see Patent Document 1).

The operator of such a tractor is required to operate the tractor whilechecking the movement of the bucket. However, the operator may beunfamiliar with the operation of the work machine, and thus a techniquethat allows the operator to operate the tractor while checking thevertical position or the angle of the bucket. Accordingly, a workvehicle that allows the operator to easily check the vertical positionor the angle of the bucket has been desired.

PRIOR ART DOCUMENT Patent Document

-   Patent Document 1: JP-A 2006-77473

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

An object of the present invention is to provide a work vehicle thatallows an operator to easily check the vertical position and the angleof bucket.

Solutions to the Problems

The problem to be solved by the invention is as described above, andmeans for solving the problem will be described below.

According to a first aspect of the present invention, there is provideda work vehicle including a work machine with a bucket, which isconfigured to freely raise/lower and rotate the bucket, the work vehiclecomprising: a display disposed near an operator seat. The display isconfigured to display vertical position information and angleinformation of the bucket.

According to a second aspect of the present invention, the display isconfigured to display the vertical position information synchronizedwith an upward/downward movement of the bucket, and to display the angleinformation synchronized with a rotational movement of the bucket.

According to a third aspect of the present invention, the display isconfigured to display vertical position setting information as an indexof the upward/downward movement of the bucket, and to display anglesetting information as an index of the rotational movement of thebucket.

According to a fourth aspect of the present invention, the displayincludes an operation section that allows operation for setting thevertical position setting information and the angle setting information.

According to a fifth aspect of the present invention, the work vehiclefurther comprises: a control section. The display includes: a displaysection configured to display in a selectable manner a plurality of thework machines that are attached to and linkable to the work vehicle, andto display in an identifiable manner one of the work machines that islinked to the work vehicle; and an operation section that allowsoperation for linking the work vehicle to one of the work machinesdisplayed on the display section. The control section cuts a linkagebetween the work vehicle and one of the work machines that is linkedthereto and makes a linkage between the work vehicle and desired one ofthe work machines when the operation section is operated to link thework vehicle to the desired one of the work machines.

Effects of the Invention

The present invention produces the effects as described below.

According to the first aspect of the present invention, the display isconfigured to display the vertical position information and the angleinformation of the bucket. This allows the operator to easily check thevertical position and the angle of the bucket.

According to the second aspect of the present invention, the display isconfigured to display the vertical position information that issynchronized with the upward/downward movement of the bucket, and todisplay the angle information that is synchronized with the rotationalmovement of the bucket. This allows the operator to easily operate thework machine while viewing the screen.

According to the third aspect of the present invention, the display isconfigured to display the vertical position setting information as anindex of the upward/downward movement of the bucket, and to display theangle setting information as an index of the rotational movement of thebucket. This allows the operator to appropriately operate the workmachine, since the operator can control the vertical position and theangle of the bucket while checking the indexes.

According to the fourth aspect of the present invention, the operatorcan easily set the vertical position setting information and the anglesetting information while viewing the display.

According to the fifth aspect of the present invention, the work vehicleincludes the sections respectively configured to operate and to displaythe linkage with the work machine. With this configuration, the operatorcan operate and confirm the settings of the linkage with the workmachine while staying in the work vehicle. This allows the operator inthe work vehicle to confirm which work machine is linked to the workvehicle and also to perform operation as to which work machine is to belinked to the work vehicle while staying in the work vehicle withoutmoving to the work machine, and thus improving the operation efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of a tractor.

FIG. 2 is a view from the arrow X in FIG. 1.

FIG. 3 is a view from the arrow Y in FIG. 1.

FIG. 4 is a view from the arrow Z in FIG. 1.

FIG. 5 shows a tractor equipped with a work machine.

FIG. 6 shows a joystick lever.

FIG. 7 shows an operator seat of the tractor and surroundings thereof.

FIG. 8 shows a view of an operator.

FIG. 9 shows an information network of the tractor.

FIG. 10 shows a display.

FIG. 11 is a diagram showing a control system relating to the display.

FIG. 12 shows a screen displayed on the display.

FIG. 13 shows a screen displayed on the display.

FIG. 14 shows a screen displayed on the display.

FIG. 15 shows a screen displayed on the display.

FIG. 16 shows a screen displayed on the display.

FIG. 17 shows an information network of the tractor.

FIG. 18 shows a connection between the tractor and the work machine thatform the information network.

FIG. 19 is a block diagram showing the information network of thetractor.

FIG. 20 shows a screen displayed on the display.

FIG. 21 shows a screen displayed on the display.

FIG. 22 shows a screen displayed on the display.

FIG. 23 shows a screen displayed on the display.

FIG. 24 shows a loader operation panel.

EMBODIMENTS OF THE INVENTION

The technical idea of the present invention can be applied to any kindsof work vehicles. The following description is made by taking an exampleof a tractor that is a representative work vehicle.

First, a tractor 1 is described below.

FIG. 1 shows the tractor 1. FIG. 2 is a view from the arrow X in FIG. 1,and FIG. 3 is a view from the arrow Y in FIG. 1. FIG. 4 is a view fromthe arrow Z in FIG. 1. Note that back and front, right and left, and topand bottom of the tractor 1 are indicated in each of the figures.

The tractor 1 mainly includes a frame 11, an engine 12, a transmission13, a front axle 14, and a rear axle 15. The tractor 1 also includes acabin 16. The inside of the cabin 16 forms an operation room thatincludes an operator seat 161, an accelerator pedal 162, a shift lever163, and the like (see FIG. 7).

The frame 11 provides a skeleton for the front part of the tractor 1.The frame 11 together with the transmission 13 and the rear axle 15 forma chassis of the tractor 1. The engine 12 described below is supportedby the frame 11.

The engine 12 converts heat energy obtained by combusting a fuel intokinetic energy. In other words, the engine 12 generates rotational powerby combusting a fuel. The engine 12 is connected with an engine controldevice (not shown). When the operator operates the accelerator pedal 162(see FIG. 7), the engine control device shifts the operation state ofthe engine 12 according to the operation by the operator. The engine 12includes an exhaust emission control device 12E. The exhaust emissioncontrol device 12E oxidizes particles, hydrocarbons, carbon monoxide,and the like included in the exhaust gas.

The transmission 13 transmits the rotational power of the engine 12 tothe front axle 14 and the rear axle 15. The transmission 13 receives therotational power from the engine 12 through a connection mechanism. Notethat the transmission 13 includes a continuously variable transmission(not shown). When the operator operates the shift lever 163 (see FIG.7), the continuously variable transmission shifts the operation state ofthe transmission 13 according to the operation by the operator.

The front axle 14 transmits the rotational power of the engine 12 tofront tires 141. The front axle 14 receives the rotational power of theengine 12 through the transmission 13. Note that a steering device (notshown) is provided along with the front axle 14. When the operatoroperates a steering wheel 164 (see FIG. 7), the steering device changesthe steering angles of the front tires 141 according to the operation bythe operator.

The rear axle 15 transmits the rotational power of the engine 12 to reartires 151. The rear axle 15 receives the rotational power of the engine12 through the transmission 13. Note that a PTO output device (notshown) is provided with the rear axle 15. When the operator operates aPTO switch 165 (see FIG. 7), the PTO output device transmits therotational power to a hauled work machine according to the operation bythe operator.

The tractor 1 is configured in such a manner that the front part thereofcan be equipped with a work machine. A front loader 80 which exemplifiesthe work machine is described below.

FIG. 5 shows the tractor 1 to which the front loader 80 is attached.FIG. 6 shows a joystick lever 8.

The front loader 80 is configured to carry earth and sand. The frontloader 80 includes frames 81, arms 82, and a bucket 83.

Each of the frames 81 is fixed to a side surface of the frame 11 with afixing tool such as a pin. Each of the frames 81 is formed to extendupwardly from the frame 11, and a bracket 81 a is attached to an upperend of each of the frames 81.

One end of each of the arms 82 is pivotally supported by the bracket 81a. Each of the arms 82 is rotatable up and down by an extendable liftcylinder 84 (see the arrow L in FIG. 5).

The bucket 83 is rotatably supported by the arms 82. The bucket 83 isrotatable up and down by an extendable rotation cylinder 85 (see thearrow R in FIG. 5).

This configuration enables upward/downward movements and a rotationalmovement of the bucket 83.

The operator freely raises/lowers and rotates the bucket 83 with thejoystick lever 8. When the operator pushes the joystick lever 8 forwardor backward, the lift cylinder 84 stretches to turn the arms 82. Whenthe operator pushes the joystick lever 8 leftward or rightward, therotation cylinder 85 stretches to rotate the bucket 83. Here, a posturein which the end of the bucket 83 is directed upward is defined as a“roll back position”. A posture in which the end of the bucket 83 isdirected downward is defined as a “dump position”. Hereinafter, adirection from the dump position to the roll back position is defined asa direction in which a rotation angle increases, and a direction fromthe roll back position to the dump position is defined as a direction inwhich the rotation angle decreases.

The joystick lever 8 is equipped with an automatic standby switch 74, anengine speed acceleration button 70, a maximum traveling speedacceleration button 71, and a maximum traveling speed decelerationbutton 72.

The operation room of the tractor 1 is described below.

FIG. 7 shows the operator seat 161 and the surroundings thereof. FIG. 8shows a view of the operator.

As described above, the inside of the cabin 16 forms the operation roomthat includes the operator seat 161, the accelerator pedal 162, theshift lever 163, and the like. A brake pedal 166, a clutch pedal 167, areverser lever 168, a speed dial 169, an instrument panel 170, and acontrol panel 171 and the like are provided around the operator seat161. The operator can control the tractor 1 by operating the acceleratorpedal 162, the shift lever 163, and the like while being seated in theoperator seat 161.

In addition, the joystick lever 8 is disposed on the right side of theoperator seat 161. The operator can control the front loader 80 byoperating the joystick lever 8 while being seated in the operator seat161.

The operator can steplessly change the speed of the traveling speed ofthe tractor 1 by tilting the shift lever 163. The instrument panel 170configured to display various conditions of the tractor 1 such as acurrent traveling speed is disposed in front of the operator seat 161.

An accelerator lever 172 and the speed dial 169 are disposed in thevicinity of the instrument panel 170. The operator can set the rotationspeed of the engine 12 by tilting the accelerator lever 172. The speeddial 169 serves as a maximum rotation speed setting dial that allows theoperator to set an upper limit of the rotation speed of the engine 12.In the case where the upper limit of the rotation speed is preset byoperation of the speed dial 169, an increase in the rotation speed ofthe engine 12 automatically stops at the preset rotation speed when theaccelerator lever 172 is operated to the fullest extent. In other words,a desired engine speed can be easily obtained and the engine speed canbe prevented from exceeding a preset value of the maximum speed byoperating the speed dial 169.

Furthermore, the tractor 1 is equipped with a display 2 in the vicinityof the operator seat 161. The display 2 is disposed on the front rightside of the operator seat 161 so that the operator can operate thedisplay 2 with the right hand. The display 2 is disposed on a sideconsole. The information network of the tractor 1 is briefly describedbelow, and the display 2 and a control system of the display 2 are alsodescribed.

FIG. 9 shows the information network of the tractor 1. FIG. 10 shows thedisplay 2. FIG. 11 shows the control system of the display 2.

The information network is spread widely to each part of the tractor 1so that the tractor 1 can exhibit maximum performance. Specifically, inaddition to the engine 12, the transmission 13, the instrument panel170, the control panel 171, and the display 2 form a controller areanetwork (CAN) to share information with one another.

In the tractor 1, the display 2 is disposed on the side console (seeFIGS. 7 and 8). The display 2 includes a liquid crystal panel 21, anencoder dial 22, and an enter button 23. The display 2 also includesfive command buttons 24, 25, 26, 27, 28. Each of the buttons isinstalled with a backlight 29 using a light emitting diode (LED) or thelike as a light source.

The liquid crystal panel 21 is provided at the center of the front faceof the display 2. The liquid crystal panel 21 is configured to display apredetermined screen according to an instruction from the control device3. For example, the liquid crystal panel 21 is configured to display anopening screen S1 according to the instruction from the control device 3(see FIG. 12). The liquid crystal panel 21 is configured to displayother screens according to instructions from the control device 3 (seeFIGS. 13 to 16). Note that the liquid crystal panel 21 may be aso-called touch screen.

The encoder dial 22 is provided on the right side of the upper surfaceof the display 2. The encoder dial 22 is configured to transmit to thecontrol device 3 an operator's intension to scroll a tab or traverse ahighlight when an element displayed on the liquid crystal panel 21 is tobe selected. For example, the encoder dial 22 is capable of transmittingto the control device 3 an operator's intension to scroll a tab when adisplayed number or alphabetical letter is to be selected (see FIG. 13).The encoder dial 22 is also capable of transmitting to the controldevice 3 an operator's intension to traverse a highlight when adisplayed icon is to be selected (see FIGS. 14 and 15).

The enter button 23 is integrated with the encoder dial 22. The enterbutton 23 is configured to transmit to the control device 3 anoperator's decision to select one of the elements displayed on theliquid crystal panel 21. For example, the enter button 23 is capable oftransmitting to the control device 3 an operator's decision to selectone of the displayed numbers or alphabetical letters (see FIG. 13). Theenter button 23 is also capable of transmitting to the control device 3an operator's decision to select one of the displayed icons (see FIGS.14 and 15). Note that the display 2 has a configuration in which theenter button 23 is pressed together with the encoder dial 22, but theconfiguration is not limited thereto. A push button may be provided onthe top surface of the encoder dial 22.

The command buttons 24, 25, 26 are provided on an upper part of thefront surface of the display 2. When a predetermined screen is displayedon the liquid crystal panel 21, the command buttons 24, 25, 26 areconfigured to transmit to the control device 3 an operator's intensionto switch the screen to another screen. When a home screen S3 isdisplayed on the liquid crystal panel 21 for example, the commandbuttons 24, 25 are capable of transmitting an operator's intension toswitch the screen to a shortcut screen (i.e., a screen arbitrarily setby the operator) to the control device 3 (see FIG. 14). When anotherhome screen S4 is displayed on the liquid crystal panel 21, the commandbutton 26 is capable of transmitting to the control device 3 anoperator's intension to switch the screen to the home screen S3 (seeFIG. 15).

The command button 27 is also provided at the upper part of the frontsurface of the display 2. Specifically, the command button 27 isdisposed next to the command button 26. Like the enter button 23, thecommand button 27 is configured to transmit to the control device 3 anoperator's decision to select one of the elements. For example, thecommand button 27 is capable of transmitting to the control device 3 anoperator's decision to select one of the displayed numbers oralphabetical letters (see FIG. 13). The command button 27 is capable oftransmitting to the control device 3 an operator's decision to selectone of the displayed icons (see FIGS. 14 and 15). In addition, thecommand button 27 is capable of transmitting to the control device 3 anoperator's intension to store the set items (see FIG. 16).

The command button 28 is also provided at the upper part of the frontsurface of the display 2. Specifically, the command button 28 isdisposed next to the command button 27. When a predetermined screen isdisplayed on the liquid crystal panel 21, the command button 28 isconfigured to transmit to the control device 3 an operator's intensionto return to the previous screen. When the home screen S4 is displayedon the liquid crystal panel 21 for example, the command button 28 iscapable of transmitting to the control device 3 an operator's intensionto return to the home screen S3 (see FIG. 15). When a loader screen S5is displayed on the liquid crystal panel 21, the command button 28 iscapable of transmitting to the control device 3 an operator's intensionto return to the home screen S4 (see FIG. 16).

The control device 3 is connected with a vertical position sensor 61 andan angle sensor 62. The vertical position sensor 61 detects the verticalposition of the bucket 83. The angle sensor 62 detects the rotationangle of the bucket 83. Detection signals from the sensors aretransmitted to the control device 3.

In the tractor 1, the lift cylinder 84 and the rotation cylinder 85operate according to the operation of the joystick lever 8. The verticalposition of the bucket 83 changes according to the operation of the liftcylinder 84, and the rotation angle of the bucket 83 changes accordingto the operation of the rotation cylinder 85. The lift cylinder 84 andthe rotation cylinder 85 operate according to the control by the controldevice 3. The lift cylinder 84 and the rotation cylinder 85 areconnected to a hydraulic circuit having a flow-path switching valve (notshown). The hydraulic circuit is connected with a pump (not shown) thatoperates by the rotational power of the engine 12.

A storage section 31 includes a non-rewritable memory such as a randomaccess read only memory (ROM), a volatile memory such as a random accessmemory (RAM), a hard disk drive, a flash memory, and the like. Thestorage section 31 stores information such as a program and a map. Aprocessing section 30 is configured to implement the program or the likestored in the ROM after reading it out onto the RAM.

The processing section 30 recognizes the detected vertical position androtation angle. Based on the these information and the informationstored in the storage section 31, the processing section 30 calculates arequired amount of operation of the lift cylinder 84 and a requiredamount of operation of the rotation cylinder 85.

Based on the results of the calculation, the control device 3 controlsthe lift cylinder 84 and the rotation cylinder 85. Specifically, thecontrol device 3 controls the opening/closing of the flow-path switchingvalve (not shown) according to the amount of operation of the joysticklever 8. Then, the amount of operation of the lift cylinder 84 and theamount of operation of the rotation cylinder 85 are adjusted accordingto the degree of opening of the flow-path switching valve.

An operation method to set the vertical position setting information asan index of the upward/downward movement of the bucket 83 and the anglesetting information as an index of the rotation operation of the bucket83 is described below.

FIGS. 12 to 16 each show a screen to be displayed on the display 2. Notethat each of the figures schematically shows only necessary parts fordescribing the present invention.

First, the opening screen S1 is displayed on the display 2 (see FIG.12). A symbol mark Sm is displayed at the center of the opening screenS1. The symbol mark Sm is a design for symbolizing a suppliermanufacturing company. The symbol mark Sm emerges out onto a blackcolored background image to make a strong impression on the operator.

Subsequently, a lock release screen S2 is displayed on the display 2(see FIG. 13). On the lock release screen S2, scroll boxes Sb1, Sb2,Sb3, Sb4 are aligned in a row for inputting a personal identificationnumber. One of the scroll boxes Sb1, Sb2, Sb3, Sb4, which has beenselected, is highlighted (see “H” in FIG. 13). Each of the scroll boxesSb1, Sb2, Sb3, Sb4 is capable of scroll-displaying numbers from 0 to 9or alphabetical letters from A to F. The operator can select one of thenumbers or the alphabetical letters by turning the encoder dial 22, andenter the selected number or alphabetical letter by pressing the enterbutton 23.

Note that on the lock release screen S2, the operator can select one ofthe numbers or the alphabetical letters by pressing the command button25 or 26, and enter the selected number or alphabetical letter bypressing the command button 27. The operator can cancel the entry bypressing the command button 28. When the input personal identificationnumber is incorrect, a message to that effect is displayed. On the lockrelease screen S2, a dialog box Db1 showing the name of the operator anda dialog box Db2 showing a work schedule are displayed. These dialogboxes Db1, Db2 allow the operator to grasp the work schedule.

Then, the display 2 displays the home screen S3 (see FIG. 14). On thehome screen S3, icons Ia1, Ia2, Ia3, Ia4, . . . , Ia8 are arranged inupper and lower two rows for selecting a menu. One of the icons Ia1,Ia2, Ia3, Ia4, . . . , Ia8, which has been selected, is highlighted (see“H” in the FIG. 14). The icons Ia1, Ia2, Ia3, Ia4, . . . , Ia8 aresequentially highlighted according to the rotation of the encoder dial22. The operator can select a desired icon (any one of the icons Ia1,Ia2, Ia3, Ia4, . . . , Ia8) by turning the encoder dial 22, and enterthe selection of the icon by pressing the enter button 23.

Note that on the home screen S3, an icon (any one of the icons Ia1, Ia2,Ia3, Ia4, . . . , Ia8) cannot be selected by pressing a command button(any one of the command buttons 24, 25, 26, 27, 28), but the selectionof the icon can be entered by pressing the command button 27. Thedisplay returns to the lock release screen S2 by pressing the commandbutton 28. In addition, when a button Ba1 marked as “previous page” or abutton Ba2 marked as “next page” is selected and entered, another homescreen S4 is displayed. The icon that cannot be selected is displayed ina grayed-out state (see “G” in FIG. 14).

Here, the button Ba2 marked as “next page” is selected and entered.

The display 2 displays the other home screen S4 (see FIG. 15). On thehome screen S4, icons Ib1, Ib2, Ib3, Ib4, . . . , Ib8 are arranged inupper and lower two rows for selecting a menu. One of the icons Ib1,Ib2, Ib3, Ib4, . . . , Ib8, which has been selected, is highlighted (see“H” in FIG. 15). The icons Ib1, Ib2, Ib3, Ib4, . . . , Ib8 aresequentially highlighted according to the rotation of the encoder dial22. The operator can select a desired icon (any one of the icons Ib1,Ib2, Ib3, Ib4, . . . , Ib8) by turning the encoder dial 22, and enterthe selection of the icon by pressing the enter button 23.

Note that on the home screen S4, an icon (any one of the icons Ib1, Ib2,Ib3, Ib4, . . . , Ib8) cannot be selected by pressing a command button(any one of the command buttons 24, 25, 26, 27, 28), but the selectionof the icon can be entered by pressing the command button 27. Thedisplay returns to the home screen S3 by pressing the command button 28.In addition, when a button Bb1 marked as “previous page” or a button Bb2marked as “next page” is selected and entered, the home screen S3 isdisplayed. The icon that cannot be selected is displayed in a grayed-outstate (not shown).

Here, the icon Ib3 marked as “loader” is selected and entered.

The display 2 displays a loader screen S5 (see FIG. 16). The loaderscreen S5 is a screen in which the vertical position information and theangle information of the bucket are displayed. On the loader screen S5,a ruler Sh and a ruler Sa are displayed. On the loader screen S5, graphsG1, G2, G3, G4 and icons Ic1, Ic2, Ic3, Ic4, Ic5 are also displayed. Theoperator can select a desired icon from the icons Ic1 to Ic5 by turningthe encoder dial 22, and enter the selection of the icon by pressing theenter button 23 or the command button 27.

The ruler Sh and the graphs G1, G2 indicate the vertical positioninformation of the bucket 83. The ruler Sh and the graphs G1, G2 arevertically displayed on the loader screen S5. The ruler Sh is displayedbetween the graph G1 and the graph G2.

The ruler Sa and the graphs G3, G4 indicate the angle information of thebucket 83. The ruler Sa and the graphs G3, G4 are laterally displayed onthe loader screen S5. The ruler Sa is displayed between the graph G3 andthe graph G4.

The graphs G1, G2, G3, G4 are so-called bar graphs. The graphs G1 and G3are displayed in white. The graphs G2 and G4 are displayed in black. Thegraphs G1, G2, G3, G4 respectively include indicators I1, I2, I3, I4.The indicators I1, I2, I3, I4 move along the respective graphs G1 G2,G3, G4. Note that the indicators I1, I2 are displayed in red. Theindicators I3, I4 are displayed in blue.

The ruler Sh indicates a range of the upward/downward movement of thebucket 83. The range indicated by the ruler Sh is a mechanically limitedrange of the upward/downward movement of the bucket 83. In other words,the ruler Sh indicates a movable range in the vertical direction of thebucket 83. The upper end of each of the graphs G1, G2 is an upper limitof the movable range, and the lower end of each of the graphs G1, G2 isa lower limit of the movable range. Note that the range indicated by theruler Sh may be a limited range in a controlled manner.

The ruler Sa indicates a range of the rotation angle of the bucket 83.The range indicated by the ruler Sa is a mechanically limited range ofthe rotational movement of the bucket 83. In other words, the ruler Saindicates a rotatable range of the bucket 83. The right end of each ofthe graphs G3, G4 is the upper limit of the rotatable range, and theleft end of each of the graphs G3, G4 is the lower limit of therotatable range. Note that the range indicated by the ruler Sa may be alimited range in a controlled manner.

The graph G1 indicates an actual vertical position of the working bucket83. The whole length of the graph G1 is equally divided into ten withrespect to the movable range of the bucket 83 in the vertical direction.The indicator I1 moves along the graph G1 in synchronization with theupward/downward movement of the bucket 83. The indicator I1 moves upwardwhen the vertical position of the bucket 83 is raised, and the indicatorI1 moves downward when the vertical position of the bucket 83 islowered.

On the other hand, the graph G3 indicates an actual angle of therotating bucket 83. The whole length of the graph G3 is equally dividedinto ten with respect to the rotatable range of the bucket 83. Theindicator I3 moves laterally along the graph G3 in synchronization withthe rotation of the bucket 83. The indicator I3 moves rightward when therotation angle of the bucket 83 increases, and the indicator I3 movesleftward when the rotation angle of the bucket 83 decreases.

In this manner, the display 2 displays the vertical position informationin synchronization with the upward/downward movement of the bucket 83,and displays the angle information in synchronization with therotational movement of the bucket 83. This allows the operator to easilycontrol the front loader 80 while viewing the screen.

The graph G2 displays the vertical position setting information. Theindicator I2 of the graph G2 indicates a vertical position as an indexof the upward/downward movement of the bucket 83. The graph G4 indicatesthe angle setting information. The indicator 14 of the graph G4indicates a rotation angle as an index of the rotational movement of thebucket 83.

The operator can set the position of the indicator I2 of the graph G2 asan index of the vertical position of the bucket 83. Note that themovement of the bucket 83 is not limited in a range of the index of thevertical position, and the bucket 83 can move beyond the range of theindex.

The operator can set the position of the indicator 14 of the graph G4 asan index of the rotation angle of the bucket 83. Note that the movementof the bucket 83 is not limited in a range of the index of the rotationangle, and the bucket 83 can move beyond the range of the index.

The icon Ic5 is used for setting an index of the vertical position andan index of the rotation angle of the bucket 83. In the case where theicon Ic5 is selected and entered while the front loader 80 is underoperation, a position detected as an actual vertical position of thebucket 83 is set as an index of the vertical position. At the same time,an angle detected as an actual rotation angle of the bucket 83 is set asan index of the rotation angle. At this time, the indicators I1 and I2are aligned laterally, and the indicators I3 and I4 are alignedvertically.

The actual vertical position of the bucket 83 is indicated by theindicator I1 of the graph G1. Accordingly, the operator can easilydetermine whether the vertical position of the bucket 83 is appropriateby comparing the indicator I1 of the graph G1 and the indicator I2 ofthe graph G2.

The actual rotation range of the bucket 83 is indicated by the indicatorI3 of the graph G3. Accordingly, the operator can easily determinewhether the angle of the bucket 83 would be appropriate by comparing theindicator I3 of the graph G3 and the indicator I4 of the graph G4.

The operator can set these indexes on the basis of a view from theoperator seat 161 while actually operating the front loader 80, forexample. Setting these indexes allows the operator to check via thedisplay 2 whether the vertical position and the rotation angle of thebucket 83 are appropriate. Accordingly, efficiency and safety of theoperation using the front loader 80 can be improved.

Note that on the loader screen S5, an icon (any one of Ic1, Ic2, Ic3,Ic4) cannot be selected by pressing a command button (any one of 24, 25,26, 27, 28), but the selection of the icon can be entered by pressingthe command button 27. When the command button 28 is pressed, the screenreturns to the home screen S4.

Note that the icons Ic1 to Ic4 are icons for switching the control stateof the front loader 80. When the icon Ic1 is selected and entered,whether the engine speed is to be changed or to be unchanged can be set.When the icon Ic2 is selected and entered, a limit of the working rangecan be set and also a predetermined range of the vertical position and apredetermined range of the rotation angle can be set. When the icon Ic3is selected and entered, a vertical position and a rotation angle of thebucket 83 for storage can be set. When the icon Ic4 is selected andentered, a link between the front loader 80 or another work machine andthe tractor 1 can be set.

Some kinds of work machines can be linked to the tractor 1. In additionto the above described front loader 80, a rotary, a sprayer, abroadcaster and the like that are to be attached to the rear part of thetractor 1 are included in the work machines that can be linked to thetractor 1. When such a work machine is attached to the tractor 1, thetractor 1 and the work machine can be linked to each other. The term“link” used herein refers to a state in which the tractor 1 worksoptimally in accordance with the movements of the work machine. The term“link” also refers to a state in which the work machine works optimallyin accordance with a state of the tractor 1. A control system thatenables such a linked state is called EcoTra-Link (hereinafter referredto as a work machine link system).

Further, the icons Ic1, Ic2, Ic3, Ic4 respectively include lamps L1, L2,L3, L4. The lamps are configured to indicate the ON or OFF of therespective settings relating to the control of the front loader 80. Forexample, when the control to automatically increase the engine speedduring the operation of the bucket 83 is effective, the lamp L1 ishighlighted in green.

In addition, when the bucket 83 moves beyond the set index of thevertical position or the rotation angle, a warning may be issued. Forexample, the display 2 may have a sound output function and output analarm sound. When the bucket 83 moves beyond the set vertical positionor rotation angle, the display 2 may display the graph G1 or G3 in acolor different from the normal color.

The work machine link system is a system in which the tractor 1 and thework machine communicate with each other bidirectionally to reduce theburden of the operator in operability, work efficiency, and the like.Referring to FIGS. 9 and 17, ECUs in the tractor 1 such as the engine12, the instrument panel (meters) 170, the transmission 13, a UFO (notshown), and the display 2, are connected with each other via a CAN andintegrally controlled.

Referring to FIG. 18, a work machine such as the front loader 80 isconnected to the tractor 1 and a variety of information is exchangedbetween the tractor 1 and the work machine to achieve a highly advancedcontrol. The information is exchanged via a CAN, and the tractor 1 andthe work machine are connected with each other through a communicationconnector 6 in compliance with the JAMMA standards (AG-PORT). Acontroller of the work vehicle (communication control unit such as aninterface and an ECU connected to CAN) and a controller of the workmachine (including another interface and ECU connected to CAN) can belinked to each other through an AG-PORT or an ISOBUS.

The work machine can be operated by operating the operation tools (suchas the above joystick lever 8, the accelerator lever 172, and the shiftlever 163) according to the state of the tractor 1. In other words, theoperation of the work machine can be assigned to the operation tools ofthe tractor 1 (main machine). This achieves integral operability betweenthe tractor 1 and the work machine. In other words, the engine rotation,PTO rotation, traveling speed, and position (the vertical position andthe inclination of the work machine) and the like can be appropriatelyadjusted according to the operation state of the work machine. In thismanner, the tractor 1 and the work machine communicate with each otherbidirectionally, and thus an integrated operation can be achieved.

Note that the operator can make various settings of the work machineattached to the tractor 1 by operating the control panel 171 of thetractor 1 (see FIG. 7). The control panel 171 is disposed behind theaccelerator lever 172, but may be disposed at another position in thevicinity of the operator seat 161.

The configuration of a CAN of the tractor 1 will be described below.

Referring to FIG. 19, the tractor 1 is provided with a CAN network. Thevarious components of the tractor 1, such as the engine 12, thetransmission 13, the display 2, the instrument panel 170, the shiftlever 163, the accelerator lever 172, and the speed dial 169 areconnected to the network. The CAN of the tractor 1 is connected with acommunication control unit 73 that is configured to performcommunication control of the network. The communication control unit 73may be included in the control device 3 (see FIG. 11).

The communication control unit 73 is configured to communicate with thecomponents of the tractor 1 (e.g., the engine 12, the transmission 13,and the like) to control the engine speed, a gear ratio of thetransmission 13, and the like. For example, the communication controlunit 73 acquires the amount of operation of the accelerator lever 172and communicates with the engine 12 to change the engine speed accordingto the amount of operation of the accelerator lever 172. With thisconfiguration, the operator can obtain a desired engine speed byoperating the accelerator lever 172. At this time, the communicationcontrol unit 73 changes the engine speed not to exceed the speed set bythe speed dial 169.

The communication control unit 73 also acquires the amount of operationof the shift lever 163 and communicates with the transmission 13. Thecommunication control unit 73 communicates with the transmission 13 tochange a tilt angle of a movable swash plate of a hydraulic pump in thecontinuously variable transmission of the transmission 13 according tothe amount of operation of the shift lever 163. With this configuration,the operator operates the shift lever 163 to continuously change therotation speed of a gear shift output shaft (not shown) of thetransmission 13. As a result, the traveling speed of the tractor 1 ischanged steplessly.

The front loader 80 is connected to the CAN of the tractor 1.Specifically, the joystick lever 8 of the front loader 80 is connectedto the components of the tractor 1 via the CAN. With this configuration,the communication control unit 73 can acquire information about theoperation of the joystick lever 8. In addition, the display 2 isconnected to the components of the tractor 1 via the CAN. Thecommunication control unit 73 can acquire information about the settingsof the front loader 80 set by the display 2.

In addition to the front loader 80, other work machines (work machine A,work machine B, etc.) can be connected to the communication control unit73. On the other hand, the communication control unit 73 can transmitinformation about the tractor 1 such as the traveling speed and theengine speed of the tractor 1, to the front loader 80 and other workmachines.

In this manner, the work machine such as the front loader 80 and thetractor 1 can communicate with each other via a CAN. With thisconfiguration, the communication control unit 73 can communicate withthe components of the tractor 1 such as the engine 12 and thetransmission 13 so as to be linked to the operation of the front loader80. In other words, the communication control unit 73 communicates withthe engine 12 and the transmission 13 so that the engine speed, the gearratio of the transmission 13 and the like can be automatically changedaccording to the amount of operation of the front loader 80.

In the tractor 1, the communication control unit 73 is configured toautomatically increase the engine speed when the load of the frontloader 80 increases at the time of the operation of the front loader 80such as lifting of the arms 82 and the rotation of the bucket 83. Withthis configuration, the operation oil supplied to the lift cylinder 84and the rotation cylinder 85 (see FIG. 11) can be automaticallyincreased when the load of the front loader 80 increases, and thus thework by the front loader 80 can be performed smoothly. The operationsthat increase the load of the front loader 80 include a case where thevertical position of the arms 82 is raised and a case where the bucket83 is operated in the roll back position.

When the joystick lever 8 of the front loader 80 is operated by theoperator, information about the amount of the operation is transmittedto the communication control unit 73. When detecting that the operationload of the front loader 80 is increased based on the acquiredinformation about the operation amount of the joystick lever 8, thecommunication control unit 73 communicates with the engine 12 toincrease the engine speed.

When detecting that the joystick lever 8 of the front loader 80 isreturned to the neutral position, the communication control unit 73communicates with the engine 12 to return the engine speed to the speedjust before the automatic increase. With this configuration, the enginespeed is automatically returned to the normal speed after the operationload of the front loader 80 is dissolved, and thus a continuous load onthe engine 12 can be prevented.

In addition, when the engine speed is automatically increased in thetractor 1, the communication control unit 73 communicates with thetransmission 13 to automatically change the gear ratio of thetransmission 13 (specifically, automatically changes the tilt angle ofthe movable swash plate). In this manner, the communication control unit73 controls the transmission 13 to maintain the rotation of the gearshift output shaft of the continuously variable transmission at aconstant speed. In other words, the communication control unit 73communicates with the transmission 13 so as to automatically change thegear ratio of the transmission 13.

Even when the communication control unit 73 communicates with the engine12 and the transmission 13 to automatically increase the engine speed, asituation where the traveling speed changes against the operator'sintension can be prevented. Therefore, the network of the CAN configuredin this manner does not require a condition to prevent a change of thetraveling speed against the operator's intension, i.e., the operation ofthe shift lever 163 to the neutral position and the operation of theclutch pedal 167 (see FIG. 7) by the operator.

As described above, the tractor 1 is configured in such a manner thatthe engine speed is increased irrespective of the condition of the shiftlever 163 in a neutral position, disconnection of the clutch, or thelike when the joystick lever 8 is operated to raise the arms 82 or tohave the bucket 83 in the roll back position. In this manner, the enginespeed can be automatically changed even when the tractor 1 is traveling,for example.

It should be noted that the engine speed cannot be changed by theoperation of the joystick lever 8 at all timings intended by theoperator. When the joystick lever 8 is in the neutral position, forexample, the communication control unit 73 does not automaticallyincrease the engine speed.

The engine speed can be surely changed at an arbitrary timing byoperating the accelerator lever 172. However, when the operator isintended to operate the accelerator lever 172 while operating thesteering wheel 164 with one hand for example, the operator has to let goof the joystick lever 8. In addition, the traveling speed changes as theengine speed is changed by the operation of the accelerator lever 172.

However, the tractor 1 is configured in such a manner that the enginespeed is increased to the maximum speed while maintaining the travelingspeed when the engine speed acceleration button 70 on the joystick lever8 is operated. When the engine speed acceleration button 70 is operated,the joystick lever 8 transmits the information to that effect to thecommunication control unit 73. When detecting the operation of theengine speed acceleration button 70, the communication control unit 73communicates with the engine 12 and the transmission 13 to increase theengine speed to the maximum speed while changing the gear ratio of thetransmission 13 so that the rotation of the gear shift output shaft ofthe continuously variable transmission is maintained at a constant speed(so as to maintain a constant traveling speed).

With this configuration, the operator can increase the engine speed atan arbitrary timing while maintaining a constant traveling speed.Operations such as the operation of the shift lever 163 into the neutralposition or stepping of the clutch pedal 167 are not required even whenthe engine speed is increased by the operation of the engine speedacceleration button 70.

Note that the communication control unit 73 increases the engine speedto a speed set by the speed dial 169. This configuration is advantageousin that the engine speed can be increased to a desired speed of theoperator with a simple operation of the engine speed acceleration button70. In addition, a situation in which the engine speed of the engine 12is unnecessarily increased can be prevented, since the upper limit ofthe engine speed is provided.

The joystick lever 8 includes a maximum traveling speed accelerationbutton 71 and a maximum traveling speed deceleration button 72 (see FIG.6) that are configured to change the maximum traveling speed. With thisconfiguration, the maximum traveling speed can be changed by theoperation of the joystick lever 8. When the maximum traveling speedacceleration button 71 or the maximum traveling speed decelerationbutton 72 are operated, the joystick lever 8 transmits the informationto that effect to the communication control unit 73. When detecting theoperation of the maximum traveling speed acceleration button 71, thecommunication control unit 73 changes the set value so as to increasethe maximum traveling speed. When detecting the operation of the maximumtraveling speed deceleration button 72, the communication control unit73 changes the set value so as to lower the maximum traveling speed.

The “maximum traveling speed” used herein refers to a set value of thetraveling speed at the time when the accelerator lever 172 is operatedto the fullest extent. For example, when the maximum traveling speed isset to be low, a change in the traveling speed relative to the amount ofoperation of the accelerator lever 172 is reduced. On the other hand,when the maximum traveling speed is set to be high, the change in thetraveling speed relative to the amount of operation of the acceleratorlever 172 is increased. Accordingly, the settings like this areadvantageous in the case where the tractor 1 travels at a relativelyhigh speed, such as at the time of traveling on a road.

A correlation between an amount of operation of the accelerator lever172 and the traveling speed is changed when a setting of the maximumtraveling speed is changed. As a result, a traveling speed correspondingto the current amount of operation of the accelerator lever 172 ischanged. Accordingly, when the setting of the maximum traveling speed ischanged, the current traveling speed changes without operating theaccelerator lever 172. In this manner, changing the setting of themaximum traveling speed can also be utilized for changing the currenttraveling speed without an operation of the accelerator lever 172.

As the operator operates the joystick lever 8 during the operationsusing the front loader 80, it is not always easy for the operator tooperate the accelerator lever 172 to change the traveling speed.However, the configuration of the present embodiment in which thejoystick lever 8 includes the maximum traveling speed accelerationbutton 71 and the maximum traveling speed deceleration button 72, allowsthe operator to easily change the traveling speed while grasping thejoystick lever 8 (without operating the accelerator lever 172).Accordingly, the operator can concentrate his/her attention on theoperation of the front loader 80.

The description now will be made on the setting of a range of increaseof the engine speed by using the display 2 instead of the speed dial169.

When the icon Ic1 is selected and entered on the loader screen S5 (seeFIG. 16), an engine speed setting screen S6 is displayed (see FIG. 20)on the display 2. The engine speed setting screen S6 is a screen forsetting the range of increase of the engine speed, which is one of thesettings of the linked operation between the tractor 1 and the frontloader 80. Boxes B1, B2 are vertically arranged on the engine speedsetting screen S6. In the box B1, “ON” (displayed in FIG. 20) or “OFF”(hidden instead of “ON” in FIG. 20) can be selected by turning theencoder dial 22. The operator turns the encoder dial 22 to select eitherof ON or OFF, and presses the enter button 23 to switch between ON andOFF.

The display of ON indicates that the setting is enabled and the enginespeed can be automatically increased with the operation of the enginespeed acceleration button 70 of the joystick lever 8 (see FIG. 6). Thedisplay of OFF indicates that the setting is not enabled and the enginespeed cannot be automatically increased even with the operation of theengine speed acceleration button 70. When the setting is enabled, thelamp L1 (see FIG. 16) is highlighted in green.

When ON is selected and entered to enable the setting, the backgroundcolor of the box B2 is changed, and the setting operation can be madewith reference to the display of the box B2. In the box B2, a graph G5,which is a bar graph, and the range of increase to be set are displayed.The left end of the graph G5 indicates a lower most value (i.e., 0) ofthe range of increase, and the right end of the graph G5 indicates anupper most value of the range of increase. The graph G5 is displayed inblack. The graph G5 indicates the range of increase of the engine speed.In the graph G5, an indicator Id1 is displayed in white. At the time ofsetting the range of increase of the engine speed, the indicator Id1extends or contracts according to the value. When a desired value isdetermined, the range of increase is set accordingly. The operator turnsthe encoder dial 22 to extend or contract the indicator Id1, and pressesthe enter button 23 to enter the value of the range of increase.

A value of the range of increase (r/min) is displayed on the right sideof the graph G5. In FIG. 20, “300 r/min” is displayed as a current setvalue. Note that the range of increase may be set even in a state wherethe setting of the range of increase of the engine speed is not enabled.

When a button Bc1 marked as “previous page” or an icon marked as“return” is selected and entered on the engine speed setting screen S6,the display returns to the loader screen S5. When a button Bc2 marked as“next page” is selected and entered, a traveling speed setting screen S7(see FIG. 21) is displayed.

The traveling speed setting screen S7 is a screen for setting a range ofincrease or reduction of the traveling speed of the tractor 1, which isone of the settings of the linked operation between the tractor 1 andthe front loader 80. Boxes B4, B5, B6 are vertically arranged in thisorder from top to bottom on the traveling speed setting screen S7. Inthe box B4, “ON” (displayed in FIG. 21) or “OFF” (hidden instead of “ON”in FIG. 21) can be selected by turning the encoder dial 22.

The display of ON indicates that the setting is enabled and thetraveling speed can be automatically increased with the operation of themaximum traveling speed acceleration button 71 of the joystick lever 8(see FIG. 6) and automatically decreased with the operation of themaximum traveling speed deceleration button 72 (see FIG. 6). The displayof OFF indicates that the setting is not enabled and the traveling speedcannot be automatically changed even with the operation of the maximumtraveling speed acceleration button 71 or the maximum traveling speeddeceleration button 72.

When ON is selected and entered to enable the setting, the backgroundcolor of the box B5 is changed, and the setting operation can be madewith reference to the display of the box B5. In the box B5, a graph G6,which is a bar graph, and the range of increase to be set is displayed.The left end of the graph G6 indicates a lower most value (i.e., 0) ofthe range of increase, and the right end of the graph G6 indicates anupper most value of the range of increase. The graph G6 is displayed inblack. The graph G6 indicates the range of increase of the travelingspeed. In the graph G6, an indicator Id2 is displayed in white. At thetime of setting the range of increase of the traveling speed, theindicator Id2 extends or contracts according to the value. When adesired value is determined, the range of increase is set accordingly.The operator turns the encoder dial 22 to extend or contract theindicator Id2, and presses the enter button 23 to enter the value of therange of increase.

When the range of increase is set, the background color of the box B6 ischanged, and the setting operation can be made with reference to thedisplay of the box B6. In the box B6, a graph G7, which is a bar graph,and the range of reduction to be set is displayed. The right end of thegraph G6 indicates an upper most value (i.e., 0) of the range ofreduction, and the left end of the graph G7 indicates a lower most valueof the range of reduction. The graph G7 is displayed in black. The graphG7 indicates the range of reduction of the traveling speed. In the graphG7, an indicator Id3 is displayed in white. At the time of setting therange of reduction of the traveling speed, the indicator Id3 extends orcontracts according to the value. When a desired value is determined,the range of reduction is set accordingly. The operator turns theencoder dial 22 to extend or contract the indicator Id3, and presses theenter button 23 to enter the value of the range of reduction.

A value of the range of increase and a value of the range of reduction(km/h) are respectively displayed on the right side of the graphs G6,G7. In FIG. 21, “+2.0 km/h” and “−3.0 km/h” are displayed as current setvalues. Note that the range of increase and the range of reduction maybe set even in a state where the setting to change the traveling speedis not enabled.

When a button Bd1 marked as “previous page” or an icon marked as“return” is selected and entered on the traveling speed setting screenS7, the display returns to the engine speed setting screen S6 (see FIG.20). When a button Bd2 marked as “next page” is selected and entered,the display returns to the loader screen S5 (see FIG. 16).

The description now will be made on an automatic standby function of thefront loader 80, which is one of the settings of the linked operation ofthe tractor 1 and the front loader 80. The automatic standby used hereinrefers to a function of automatically setting the bucket 83 and the arms82 at a set angle and a set vertical position respectively. The arms 82and the bucket 83 are suspended after automatically moved to therespective set positions, thereby reducing the operation of the joysticklever 8 by the operator.

When the icon Ic3 is selected and entered on the loader screen S5 (seeFIG. 16), an automatic standby setting screen S8 is displayed on thedisplay 2 (see FIG. 22). The automatic standby setting screen S8 is ascreen for enabling or not enabling the automatic standby function. Theangle of the bucket 83 and the vertical position of the arms 82 duringthe automatic standby state can also be set on the automatic standbysetting screen S8. On the automatic standby setting screen S8, a box B7is displayed. In the box B7, “ON” (displayed in FIG. 22) or “OFF”(hidden instead of “ON” in FIG. 22) can be selected by turning theencoder dial 22.

The display of ON indicates that the setting is enabled and the frontloader 80 can be automatically moved to the set position for storagewith the operation of the automatic standby switch 74 of the joysticklever 8 (see FIG. 6). The display of OFF indicates that the setting isnot enabled and the front loader 80 cannot be automatically moved to theset position for storage even with the operation of the automaticstandby switch 74. When the setting is enabled, the lamp L3 (see FIG.16) is highlighted in green.

Note that the tractor 1 configured to be equipped with the front loader80 has a floating function. The floating function, which is a functionof automatically following (floating) the irregularities of theworkplace, eliminates the need for complicated operations of thejoystick lever 8 by the operator to adjust the angle of the bucket 83and the vertical position of the arms 82. When the floating function isenabled, a predetermined lamp on the display 2 is highlighted forexample in green.

On the automatic standby setting screen S8, a ruler Sh2, a ruler Sa2,and graphs G21, G22, G23, G24 are displayed.

The ruler Sh2 and the graphs G21, G22 indicate the vertical positioninformation of the bucket 83. The ruler Sh2 and the graphs G21, G22 arevertically arranged on the automatic standby setting screen S8. Theruler Sh2 is displayed between the graph G21 and the graph G22.

The ruler Sa2 and the graphs G23, G24 indicate the angle information ofthe bucket 83. The ruler Sa2 and the graphs G23, G24 are laterallyarranged on the automatic standby setting screen S8. The ruler Sa2 isdisplayed between the graph G23 and the graph G24.

The graphs G21, G22, G23, G24 are so-called bar graphs. The graphs G21and G23 are displayed in white. The graphs G22 and G24 are displayed inblack. The graphs G21, G22, G23, G24 respectively include indicatorsI21, I22, I23, I24. The indicators I21, I22, I23, I24 move along therespective graphs G21, G22, G23, G24. Note that the indicators I21 andI23 are displayed in different colors from each other. The indicator I22and the indicator I24 are displayed in different colors from each other.

The graph G21 indicates the vertical position of the arms 82 forstorage, and is used to determine the set position. The indicator I21moves along the graph G21 according to the set position at the time ofsetting the vertical position of the arms 82 for storage. The operatorturns the encoder dial 22 to move the indicator I21, and presses theenter button 23 to determine the set position. The indicator I22displayed on the graph G22 indicates the current set position of thearms 82 for storage. When the set position of the arms 82 is determined,the position of the indicator I22 of the graph G22 is replaced by thedetermined position corresponding to the indicator I21 of the graph G21(see indicator I22 shown in the form of dashed lines in FIG. 22).

On the other hand, the graph G23 indicates the angle of the bucket 83for storage, and is used to determine the set angle. The indicator I23moves along the graph G23 according to the set angle at the time ofsetting the angle of the bucket 83 for storage. The operator turns theencoder dial 22 to move indicator I23, and presses the enter button 23to determine the set angle. The indicator I24 displayed on the graph G24indicates the current set angle of the bucket 83 for storage. When theset angle of the bucket 83 is determined, the position of the indicatorI24 of the graph G24 is replaced by the determined positioncorresponding to the indicator I23 of the graph G23 (see the indicatorI24 shown in the form of dashed lines in FIG. 22).

When an icon marked as “return” is selected and entered on the automaticstandby setting screen S8, the display returns to the loader screen S5(see FIG. 16).

On the other hand, when an icon Ic4 is selected and entered on theloader screen S5 (see FIG. 16), a work machine linkage screen S9 isdisplayed on the display 2 (see FIG. 23). On the work machine linkagescreen S9, three icons Ie1, Ie2, Ie3, each of which shows the name of awork machine and the display of ON or OFF, are displayed.

The icons Ie1, Ie2, Ie3 form a list of work machines that are linkableto the tractor 1. The icons Ie1 and Ie2 respectively indicate thelinkable work machines that are attached to the tractor 1, and aredisplayed in a selectable manner. The green lamp LG is turned on in theicon Ie1. On the other hand, the icon Ie3 indicates a work machine thatis linkable to but is not attached to the tractor 1, and is displayed inan unselectable manner. The icon Ie3 is displayed in gray which meansthe icon cannot be selected. The icon Ie3 cannot be selected by turningthe encoder dial 22.

Accordingly, the operator turns the encoder dial 22 to select desiredone of the icons Ie1 and Ie2 on the work machine linkage screen S9, andpresses the enter button 23 to switch between ON and OFF. The display ofON indicates that the work machine is linked to the tractor 1, and thedisplay of OFF indicates that the work machine is not linked to thetractor 1.

Referring to FIG. 23, the icon Ie3 cannot be selected. When either theicon Ie1 or the icon Ie2 is determined, if any one of the work machinesis linked to the tractor 1, the display of one of the icons Ie1 and Ie2corresponding thereto is changed from ON to OFF to indicate the workmachine is not in a linked state, and the display of the icon Ie1 or Ie2corresponding to the determined one of the work machine is changed fromOFF to ON to indicate that the work machine is in a linked state. Onlyone work machine is linked to the tractor 1 at a time.

As shown in FIG. 23, when the setting is enabled through the icon Ie1 tolink the front loader 80 to the tractor 1 (main device), the lamp L4(see FIG. 16) is highlighted in green. When any one of the work machinesis set to be linkable to the tractor 1 (main device), a lamp on theinstrument panel 170 (see FIG. 9) is turned on to indicate the linkablework machine. Note that the display of the lamp includes the same figureas that included in the icon Ic4 (see FIG. 16).

Note that the range of increase of the engine speed, the range ofincrease and reduction of the traveling speed, the automatic standbystate, the floating function, and the linkage operation with the workmachine to have the front loader 80 be linked to the tractor 1 can alsobe set by using the loader operation panel 50. Referring to FIG. 19, theloader operation panel 50 is connected to each component of the tractor1 via the CAN. The loader operation panel 50 can be disposed in thevicinity of the operator seat 161.

The loader operation panel 50 disposed in the vicinity of the display 2as shown in FIG. 24 allows the operator to easily make the varioussettings while checking the information displayed on the display 2. Theloader operation panel 50 includes a linkage button 75.Enablement/non-enablement of functions to link the front loader 80 tothe tractor 1 can be collectively set with the linkage button 75. Whenthe operator presses the linkage button 75, the communication controlunit 73 collectively enables a plurality of functions to link the frontloader 80 to the tractor 1, and collectively disables a plurality offunctions to link another work machine to the tractor 1. When thelinkage button 75 is pressed again, the communication control unit 74comprehensively turns off the plurality of functions to link the frontloader 80 with the tractor 1.

In view of the above, the plurality of functions to link the frontloader 80 to the tractor 1 can be collectively switched between anenabled state and a non-enabled state by simply operating the linkagebutton 75. Note that a lamp L5 is provided on the left side of thelinkage button 75. The lamp L5 is turned off when the linkage with thetractor 1 is not enabled, and is turned on when the linkage with thetractor 1 is enabled. The state of the lamp L5 allows the operator tovisually confirm the linkage state between the front loader 80 and thetractor 1.

The loader operation panel 50 also includes setting buttons 76, 77, 78,79 allotted for respective functions. The setting button 76 is anoperation tool configured to enable or disenable the function of theautomatic increase of the engine speed. The setting button 77 is anoperation tool configured to enable or disenable the floating function.The setting button 78 is an operation tool configured to enable ordisenable the automatic standby function. The setting button 79 is anoperation tool configured to enable or disenable the other function. Theother function includes a setting of the vertical position settinginformation and the angle setting information of the front loader 80.

When one of the setting buttons 76, 77, 78, 79 is operated, thecommunication control unit 73 enables or disenables only a functioncorresponding to the one of the setting buttons 76, 77, 78, 79 among thefunctions to link the front loader 80 to the tractor 1.

Note that lamps L6, L7, L8, L9 are arranged on the left side the settingbuttons 76, 77, 78, 79, respectively. The lamps L6, L7, L8, L9 areturned off when the functions corresponding to the respective settingbuttons 76, 77, 78, 79 are disenabled, and are turned on when thefunctions corresponding to the respective setting buttons 76, 77, 78, 79are enabled. The lamp L9 is turned off when the function of setting thevertical position setting information and the angle setting informationof the front loader 80 is disenabled, and turned on when this functionis enabled. When the function of setting the vertical position settinginformation and the angle setting information of the front loader 80 isenabled, the lamp L2 (see FIG. 16) on the display 2 is also switchedfrom a turned-off state to a turned-on state. In the same manner, thelamps L1, L3 are turned off when the functions corresponding to thesetting buttons 76, 78 are disenabled, and the lamps L1, L3 are turnedon when these functions are enabled.

INDUSTRIAL APPLICABILITY

The present invention is applicable to a work vehicle having a display.

DESCRIPTION OF REFERENCE SIGNS

-   1: tractor (work vehicle)-   2: display-   3: control device (control section)-   80: front loader (work machine)-   83: bucket-   G1: graph (vertical position information)-   G2: graph (vertical position information)-   G3: graph (angle information)-   G4: graph (angle information)-   I1: indicator (synchronized vertical position information)-   I2: indicator (vertical position setting information)-   I3: indicator (synchronized angle information)-   I4: indicator (angle setting information)-   S5: loader screen-   S6: engine speed setting screen-   S7: traveling speed setting screen-   S8: automatic standby setting screen-   S9: work machine linkage screen

The invention claimed is:
 1. A work vehicle including a work machinewith a bucket, which is configured to freely raise/lower and rotate thebucket, the work vehicle comprising: a display disposed near an operatorseat, wherein: the display is configured to: concurrently displayvertical position information and angle information, wherein thevertical position information is synchronized with an upward/downwardmovement of the bucket, and wherein the angle information of the bucketis synchronized with a rotational movement of the bucket, and display ascreen for enabling or not enabling an automatic standby function ofautomatically setting the bucket at a set angle and a set verticalposition respectively.
 2. The work vehicle according to claim 1, whereinthe display is further configured to display: vertical position settinginformation as an index of the upward/downward movement of the bucket,and to display angle setting information as an index of the rotationalmovement of the bucket.
 3. The work vehicle according to claim 2,wherein: the display includes an operation section that allows operationfor setting the vertical position setting information and the anglesetting information.
 4. The work vehicle according to claim 1, furthercomprising: a control section, wherein: the display includes a displaysection configured to display in a selectable manner, a plurality ofwork machines that are attached to and linkable to the work vehicle, andto display in an identifiable manner one of the work machines that islinked to the work vehicle; and an operation section that allowsoperation for linking the work vehicle to one of the work machinesdisplayed on the display section, and the control section cuts a linkagebetween the work vehicle and one of the work machines that is linkedthereto and makes a linkage between the work vehicle and desired one ofthe work machines when the operation section is operated to link thework vehicle to the desired one of the work machines.
 5. The workvehicle according to claim 1, wherein: the vertical position informationcomprises a first vertical indicator configured to move upward ordownward on the display in synchronization with an upward/downwardmovement of the bucket; and the angle information comprises a firstrotational indicator configured to move left or right on the display insynchronization with a rotational movement of the bucket.
 6. The workvehicle according to claim 5, wherein the display is further configuredto display: vertical position setting information that comprises asecond vertical indicator as a vertical index of the upward/downwardmovement of the bucket; and angle setting information that comprises asecond rotational indicator as rotational index of the rotationalmovement of the bucket.
 7. The work vehicle according to claim 6,wherein: the vertical index comprises a predetermined range based on thesecond vertical indicator; and based on the first vertical indicatormoving outside the predetermined range, the display is configured tooutput a notification.
 8. The work vehicle according to claim 6,wherein: the display includes an operation section that is selectableand allows operation for setting the vertical index and the rotationalindex.
 9. The work vehicle according to claim 8, wherein: the firstvertical indicator is configured to move upward on the display based ona vertical position of the bucket being raised, and move downward on thedisplay based on the vertical position of the bucket being lowered; andthe first rotational indicator is configured to move rightward on thedisplay based on an increase in a rotation angle of the bucket, and moveleftward on the display based on a decrease in the rotation angle of thebucket.
 10. The work vehicle according to claim 9, wherein, based onselection of the operation section, the display is configured to: setthe second vertical indicator to correspond to a vertical position ofthe bucket; and set the second rotational indicator to correspond to arotation angle of the bucket; wherein: the second vertical indicator isconfigured to not move with the upward/downward movement of the bucket;and the second rotational indicator is configured to not move with therotational movement of the bucket.
 11. The work vehicle according toclaim 1, further comprising: a control device, wherein: the display isfurther configured to display: a work machine linkage view thatpresents: in a selectable manner, a plurality of work machines that areattached to and linkable to the work vehicle; and in an identifiablemanner, one of the plurality of work machines that is linked to the workvehicle; and an automatic standby setting view that allows operation forlinking the work vehicle to one of the work machines presented via thework machine linkage view, and the control device is configured to,based on a selection to link the work vehicle to a particular one of thework machines of the plurality of work machines: remove a linkagebetween the work vehicle and one of the work machines that is linkedthereto; and establish a linkage between the work vehicle and theparticular one of the work machines.
 12. The work vehicle according toclaim 1, wherein the screen for enabling or not enabling the automaticstandby function of automatically setting the bucket at the set angleand the set vertical position comprises a standby view.
 13. The workvehicle according to claim 1, wherein the display includes one or moreicons configured to be selected by an operator.
 14. The work vehicleaccording to claim 13, wherein the one or more icons include: a firsticon is configured to display an automatic standby setting screen whenselected by an operator in which an automatic standby function can beenabled or disabled; a second icon is configured to display a workmachine linkage screen in which a plurality of work machines that areattached to the work vehicle are displayed such that an operator canselect one of the plurality of work machines to be linked to thedisplay; and a third icon configured to enable or disable a floatingfunction.